CN113123747A - Anti-seize hydraulic anchor - Google Patents

Abstract

The invention provides an anti-sticking hydraulic anchor, which comprises a central tube and also comprises: an anchoring mechanism comprising slips movable in a radial direction of the base pipe to anchor or un-anchor; a hydraulic actuating mechanism for driving the slips to anchor; a first release mechanism for applying a force to the hydraulic actuator mechanism to move it away from the slips; and a second disanchoring mechanism for unlocking the base pipe relative to the anchoring mechanism to allow axial movement of the base pipe relative to the anchoring mechanism. The anti-blocking hydraulic anchor can overcome the problems that the conventional anti-blocking hydraulic anchor is easy to leak in a sealing way and is difficult to detach due to the fact that a fluke is blocked when the conventional anti-blocking hydraulic anchor is applied to an ultrahigh-temperature and ultrahigh-pressure acidic oil-gas field, has the advantages of being reliable in sealing, capable of repeatedly anchoring, capable of guaranteeing reliability through multiple anchor detaching modes and the like, and is suitable for the ultrahigh-temperature and ultrahigh-pressure acidic oil-gas field.

Description

Anti-seize hydraulic anchor

Technical Field

The invention relates to the technical field of downhole tools, in particular to an anti-blocking hydraulic anchor.

Background

Some known high-temperature and high-pressure acid gas reservoirs have the characteristics of easy reservoir leakage, high corrosive fluid content, low H2S content and high acid fracturing construction difficulty. In the construction process of acid fracturing, production and tubular column operation, the conventional anti-blocking hydraulic anchor has the conditions that the anti-blocking hydraulic anchor is easy to leak, an anchor fluke is easy to damage, the anchoring effect is poor, the later-stage anchor releasing is difficult and the like.

The conventional anti-blocking hydraulic anchor adopts an anchor fluke structure, and the number of dynamic seal assemblies is as high as 6-12, so that the leakage risk points are more. Furthermore, the O-ring structure limits the seal assembly to a weak point. In addition, the conventional anti-blocking hydraulic anchor is single in anchor releasing form, the anchor jaw is large in anchor releasing difficulty, once the anchor jaw is blocked, the anchor jaw cannot be recovered, and the packer cannot be unsealed.

In conclusion, the traditional anti-blocking hydraulic anchor cannot meet the construction requirements of the acidification blockage removal and acid fracturing transformation process. Therefore, the anti-blocking hydraulic anchor suitable for the ultrahigh-temperature and ultrahigh-pressure acidic oil and gas field should have the following characteristics: (1) the sealing reliability is higher under the high-temperature and high-pressure environment; (2) the anchoring force is strong, and the damage to the sleeve is small; (3) the anchoring function can be repeatedly realized by once well entry; (4) easy to release the anchoring.

Disclosure of Invention

The present invention aims to provide an anti-seize hydraulic anchor which solves at least some of the above mentioned technical problems.

According to an embodiment of the present invention, there is provided an anti-seize hydraulic anchor, including a central tube, the anti-seize hydraulic anchor further including: an anchoring mechanism comprising slips movable in a radial direction of the base pipe to anchor or un-anchor; a hydraulic actuating mechanism for driving the slips to anchor; a first release mechanism for applying a force to the hydraulic actuator mechanism to move it away from the slips; and a second disanchoring mechanism for unlocking the base pipe relative to the anchoring mechanism to allow axial movement of the base pipe relative to the anchoring mechanism.

The anti-blocking hydraulic anchor provided by the invention can be applied to the development of ultra-high temperature, ultra-high pressure and ultra-deep wells. This anti-sticking hydraulic pressure hydraulic anchor possesses two kinds of anchor modes of separating, and convenient the selection can effectively solve anti-sticking hydraulic pressure hydraulic anchor fluke card and die, the difficult problem of separating the anchor, improves and knows the success rate of removing the anchor.

In some embodiments, the side of the slips facing the base pipe is formed with two oppositely disposed ramps; the hydraulic actuating mechanism includes: a first cone for moving in an axial direction of the base pipe to drive the slips, the first cone having a tapered surface adapted to one of the two tapered surfaces; and a second vertebral body disposed opposite the first vertebral body, the second vertebral body having a taper adapted to the other of the two bevels.

The slip related to by the invention is a bidirectional slip, in particular to a sheet bidirectional slip. The anchoring force of the bidirectional slip is strong, and the damage to a casing is small. The bidirectional anchoring realized by the bidirectional slip and the two centrums of the hydraulic driving mechanism in a matching way can bear the axial tension and the axial compression of the anti-blocking hydraulic anchor pipe column, and has better strength and anchoring stability.

In some embodiments, the hydraulic actuation mechanism comprises: a hydraulic cylinder connected to the center tube, an inner cavity of the hydraulic cylinder being in fluid communication with an internal oil passage of the center tube; a piston rod connected to a first vertebral body; and a first temporary lock for holding the piston rod stationary relative to the hydraulic cylinder, the first temporary lock being breakable to allow the piston rod to move in the axial direction of the center tube.

The hydraulic automatic anchoring of the anti-blocking hydraulic anchor can be realized through the hydraulic actuating mechanism, and the structure is simple and easy to implement. The first temporary locking piece can ensure that the piston rod cannot accidentally move to push out the slip when the anti-blocking hydraulic anchor is not put into use or put into use but is not anchored, and the slip is kept in a withdrawing state, so that the smoothness of the surface of the anti-blocking hydraulic anchor and the smoothness of the lowering are ensured. When anchoring is required, the first temporary lock may be broken, for example by an external force, to enable the piston rod to move to drive the slips out and anchor.

In some embodiments, the first temporary lock is a shear pin that connects the piston rod to the base pipe. The shear pin can be disconnected when the external force reaches a set value or a threshold value, so that the piston rod is allowed to move.

In some embodiments, the first anchorages mechanism comprises: a spring housing connected to the hydraulic cylinder; and a return spring sandwiched between the spring housing and the piston rod.

After the pressure in the hydraulic actuating mechanism is discharged, the return spring can drive the piston rod to retract and return towards the hydraulic cylinder. The pressure relief automatic resetting and anchor releasing of the slips can be realized through the return spring. The hydraulic automatic anchoring and the pressure relief automatic resetting anchor releasing are combined, so that the slips can realize automatic anchoring-anchor releasing actions for multiple times, the anti-blocking hydraulic anchor can be recycled for multiple times, and multiple effective anchoring can be realized.

In some embodiments, the second anchorages mechanism comprises: a sleeve connected to the center tube and having a resilient detent; a temporary holding sleeve embedded in the sleeve; a second temporary locking member for connecting the elastic pawl and the temporary holding sleeve; wherein the elastic pawl is clamped between the second cone and the temporary holding sleeve, and a stop fit in the axial direction of the central tube is formed between the elastic pawl and the second cone, and the second temporary locking piece can be broken to allow the elastic pawl to be separated from the temporary holding sleeve and the second cone.

Besides the pressure relief and automatic reset anchor release, the invention provides another forced anchor release mode by external force (such as throwing and pressing). By means of the second temporary locking element in cooperation with the axial stop, the sleeve together with the resilient detent is axially locked by the second cone and the temporary holding sleeve, and thus the central tube. Once the second temporary locking element is broken, for example by an external force, the resilient detent can be disengaged from the axial stop of the second cone due to the resilient deformation, thereby disengaging the second cone and the temporary retaining sleeve, and the central tube is axially unlocked. At the moment, the central pipe can be pulled to drive the hydraulic actuating mechanism to be separated from the slips, the slips are allowed to be withdrawn, and the anchoring of the anti-blocking hydraulic anchor is released.

The two anchor releasing modes provided by the invention can be selected according to needs, so that the anchor releasing mode is more flexible, the application range of the anti-blocking hydraulic anchor is expanded, and the anchor releasing success rate is also improved.

In some embodiments, the second temporary lock is a shear pin that secures the resilient detent to the temporary holding sleeve. The shear pin may be disconnected when the external force received reaches a set value or threshold, thereby allowing the temporary retention sleeve to move relative to the resilient pawl.

In some embodiments, the temporary holding sleeve has a tapered ball seat at an end thereof adjacent the central tube for receiving a ball inserted into the temporary holding sleeve. The second temporary locking member may be broken by dropping a ball into the ball seat of the temporary holding sleeve and continuously applying pressure to the ball, so that the temporary holding sleeve is disengaged from the elastic click. The method for breaking the anchor by throwing the ball has simple structure and easy implementation, and can ensure that the anchor breaking is carried out smoothly.

In some embodiments, the outer wall of the temporary holding sleeve is formed with a stop surface; the anti-blocking hydraulic anchor comprises a lower joint which is sleeved on the second vertebral body and tightly abuts against the second vertebral body, and the inner wall of the lower joint is provided with a stopping step which can be formed with a stopping surface and is matched with the axial stopping of the central tube. The temporary holding sleeve is moved in the axial direction of the center tube and away from the center tube after disengaging the elastic pawls. When contacting the stop step, the temporary retaining sleeve stops moving due to the axial stop action between the stop surface and the stop step. Therefore, the temporary retaining sleeve can be prevented from being separated from the anti-blocking hydraulic anchor, and can be recovered for recycling.

In some embodiments, the anti-seize hydraulic anchor comprises an upper joint sleeved on the central pipe, and a gasket is arranged between the upper joint and the hydraulic actuating mechanism; and sealing rings are respectively arranged between the upper joint and the central pipe, between the hydraulic actuating mechanism and the central pipe, between the sleeve and the second cone, between the second cone and the lower joint and between the lower joint and the temporary holding sleeve.

These seals and gaskets are arranged axially along the central tube. Through the combined sealing of the gasket and the sealing ring, the sealing reliability is ensured. The anti-blocking hydraulic anchor has larger axial space, and a better sealing effect can be realized by combining a plurality of sealing modes.

Preferred features of the invention are described in part below and in part will be apparent from the description.

Drawings

Embodiments of the present disclosure are described in detail below with reference to the attached drawing figures, wherein:

FIG. 1 is an axial cross-sectional view of an anti-seize hydraulic anchor according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in detail below with reference to the following detailed description and accompanying drawings. The exemplary embodiments and descriptions of the present invention are provided to explain the present invention, but not to limit the present invention.

FIG. 1 shows an axial cross-sectional view of an anti-seize hydraulic power anchor according to an embodiment of the present invention. As shown in the figure, the anti-sticking hydraulic anchor 1 comprises a central pipe 4, an upper joint 2 and a lower joint 9 which are positioned at two opposite ends of the central pipe 4, an anchoring mechanism 7 which can realize the anchoring or the de-anchoring of the anti-sticking hydraulic anchor 1, a hydraulic actuating mechanism 5 which is used for driving the anchoring mechanism 7 to carry out the anchoring, and a first de-anchoring mechanism 6 and a second de-anchoring mechanism 8 which are used for enabling the hydraulic actuating mechanism 5 to leave the anchoring mechanism 7 to realize the de-anchoring of the anti-sticking hydraulic anchor 1.

The upper joint 2 is fitted over the first end of the central tube 4. Preferably, a sealing ring 22 is pressed between the upper joint 2 and the central tube 4. The upper joint 2 is also provided with a pressure relief opening.

A hydraulic actuator 5 is arranged on the central tube 4. In the embodiment shown, the hydraulic actuator 5 comprises a hydraulic cylinder 51 which is fitted over the central tube 4 and a piston rod 52 which is adapted to the hydraulic cylinder 51. The hydraulic cylinder 51 may for example be in the form of a cylinder jacket which is fitted over the central tube 4 and the inner wall of which encloses the inner chamber of the hydraulic cylinder 51 with the outer wall of the central tube 4. The internal chamber of the hydraulic cylinder 51 is in fluid communication with the internal oil circuit of the central tube 4 through an inlet orifice formed in the central tube 4. Preferably, a sealing ring 511 is pressed between the hydraulic cylinder 51 and the central tube 4. A first end of the piston rod 52 is located in the interior of the hydraulic cylinder 51 and a second end opposite the first end extends out of the hydraulic cylinder 51. The piston rod 52 is fixed to the center tube 4 by a first temporary locking member 56. Preferably, a sealing ring 522 is provided between the piston rod 52 and the central tube 4. When the first temporary lock 56 is broken, the piston rod 52 can move in the axial direction of the center pipe 4 with respect to the hydraulic cylinder 51. The first temporary lock 56 may be, for example, a shear pin that shears when an external force is applied to a set point or threshold. Preferably, the number of the first temporary locking pieces 56 may be 1 to 10, which are arranged at intervals in the circumferential direction of the center pipe 4. The manner of breaking the first temporary lock 56 may be, for example, shearing or breaking a shear pin. Preferably, a seal ring 521 is pressed between the piston rod 42 and the hydraulic cylinder 51. The second end of the piston rod 52, which extends out of the hydraulic cylinder 51, is connected, for example by means of a screw thread, with a first cone 53, while a second cone 54 is arranged outside the central tube 4 opposite the first cone 53. The sides of the first cone 53 and the second cone 54 facing away from the center tube 4 are each formed with a tapered surface, and the distance between the tapered surface of the first cone 53 and the tapered surface of the second cone 54 gradually increases in a direction away from the center tube 4. In some embodiments, a gasket 21, for example a rubber gasket, is pressed between the upper joint 2 and the hydraulic actuating mechanism 5.

In some embodiments, a press cap 3 is provided externally on the upper joint 2, the press cap 3 being connected to the upper joint 2 or the central tube 4, for example by means of a shear pin 31. The pressure cap 3 can be screwed to the hydraulic cylinder 51 and press the gasket 21 against the outer wall of the central tube 4.

The anchoring mechanism 7 is arranged between a first vertebral body 53 and a second vertebral body 54 of the hydraulic actuating mechanism 5. As shown, the anchoring mechanism 7 includes slips 71 between the first and second cones 53, 54, a slip sleeve 72 covering the slips 71 and connected to the first cone 53, and a return spring 73 sandwiched between the slip sleeve 72 and the slips 71. The slips 71 are formed with two inclined surfaces facing each other on the side facing the center pipe 4, wherein the inclined state of the first inclined surface is the same as the inclined state of the tapered surface of the first cone 53, and the inclined state of the second inclined surface is the same as the inclined state of the tapered surface of the second cone 54, so that the first cone 53 can be wedged between the first inclined surface and the center pipe 4, and the second cone 54 can be wedged between the second inclined surface and the center pipe 4. When the first temporary locking element 56 is broken so that the first cone 53 can move in a direction close to the slips 71 under the driving of the piston rod 52, the slips 71 can be lifted by the first cone 53 and the second cone 54 due to the existence of the two slopes, move in a radial direction of the base pipe 4 and move away from the base pipe 4, and can be protruded through the opening of the slip sleeve 72 to achieve anchoring. The extendable ends of the slips 71 are provided with structures to enhance anchoring, such as corrugated structures. The slip sleeve 72 may be attached to the first vertebral body 53, for example, by a fixation pin 74. The return spring 73 is used for driving the slips 71 to move in the radial direction of the central pipe 4 and close to the central pipe 4 when the anchoring is released, so that the slip sleeve 72 is retracted to release the anchoring.

The first anchorages-releasing mechanism 6 is connected to the hydraulic drive mechanism 5 for driving the piston rod 52 in a direction away from the anchorages-releasing mechanism 7 to allow anchorages-releasing of the anchorages-releasing mechanism 7. In the embodiment shown, the first anchorages-removing mechanism 6 comprises a spring housing 61 connected to the hydraulic cylinder 51, for example by means of a screw thread, and a return spring 62 sandwiched between the spring housing 61 and the piston rod 52. The direction of movement of the piston rod 52 in the axial direction of the central tube 4 depends on the comparison between the spring force applied to the piston rod 52 by the return spring 62 and the pressure applied to the piston rod 52 by the hydraulic oil in the hydraulic cylinder 51. When the oil pressure increases so that the pressure in the hydraulic cylinder is greater than the spring force, the piston rod 52 together with the first cone 53 extends in a direction approaching the slips 71, so that the slips 71 extend from the slip sleeve 72 and are anchored. When the oil pressure is removed so that the pressure in the hydraulic cylinder is less than the spring force, the piston rod 52 together with the first cone 53 is pushed away from the slips 71 by the return spring 62 to allow the slips 71 to retract and break the anchor. The decompression actuating mechanism 5 is matched with the first anchor releasing mechanism 7, so that hydraulic automatic anchoring and decompression automatic anchor releasing of the anchoring mechanism 7 can be realized.

In some embodiments, not shown, the cylinder may be configured as a bi-directional cylinder, i.e. a piston is provided within the cylinder that separates the interior of the cylinder into two chambers, which are not in fluid communication. A piston rod for driving the first vertebral body is connected to the piston. The piston rod may be pushed to extend or retract by the difference in oil pressure in the two chambers, thereby withdrawing or allowing the slips to retract. In this way, the hydraulic actuating mechanism and the first anchor releasing mechanism are integrated, and hydraulic automatic anchoring and pressure relief automatic reset anchor releasing can be realized.

In addition to the first releasing mechanism 6 for releasing pressure and automatically resetting the releasing anchor, in the illustrated embodiment, the anti-sticking hydraulic anchor 1 is further provided with a second releasing mechanism 8 for forcibly releasing the anchor by external force. As shown, the sleeve 81 of the second anchorages releasing mechanism 8 is threaded, for example, at the second end of the central tube 4. The sleeve 81 may be entirely resilient and provided with resilient detents 811 at the end remote from the central tube 4. Alternatively, the sleeve 81 may be partly more rigid (or not elastically deformable) and provided with a resilient detent 811 at the end remote from the central tube 4. Preferably, a sealing ring 812 is pressed between the sleeve 81 and the central tube 4. A temporary holding sleeve 82 is embedded in the sleeve 81. In some embodiments, the inner wall of the sleeve 81 is formed with a radial projection 813, and the central tube 4 and the temporary holding sleeve 82 abut against the radial projection 813 at opposite sides of the radial projection 813, respectively. A tapered ball seat for receiving the inserted ball is provided in the inner cavity of the temporary holding sleeve 82. A conical ball seat is provided, for example, at the end of the temporary holding sleeve 82 close to the central tube 4. A seal groove is provided at a position approximately in the middle of the temporary holding sleeve 82. The end of the temporary holding sleeve 82 remote from the central tube 4 is provided with a groove for discharging debris, for example a waist-shaped groove. The elastic click 811 and the temporary holding sleeve 82 are connected together by the second temporary locking piece 83. The second temporary locking piece 83 can be broken as necessary to enable the elastic pawl 811 to disengage from the temporary holding sleeve 82. The second temporary locking member 83 may be, for example, a shear pin. The shear pin may shear when the applied external force reaches a preset value or threshold.

When the second temporary locking member 83 is not broken, the resilient pawl 811 is sandwiched between the second cone 54 and the temporary holding sleeve 82, and the resilient pawl 811 cooperates with the second cone 54 to form a stop in the axial direction of the center tube 4. For example, a portion of the resilient detent 811 projects away from the center tube 4 to form a stop boss 814, such that the resilient detent 811 is L-shaped and the end of the second cone 54 rests against the stop boss 814 and forms an axial stop fit with the stop boss 814. Preferably, a seal 815 is compressed between the sleeve 81 and the second cone 54. In some embodiments, the ends of the resilient detent 811 may be provided with milled grooves.

The lower fitting 9 fits over the second cone 54 and the temporary holding sleeve 82 near the second end of the center tube 4. The lower connector 9 is pressed against the second vertebral body 54 by the tightening pin 91. Preferably, a sealing ring 92 is compressed between the lower connector 9 and the second cone 54. Preferably, a sealing ring 93 is pressed between the lower joint 9 and the temporary holding sleeve 82. It is further preferred that there are a plurality of, for example 4, sealing rings 93 between the lower joint 9 and the temporary holding sleeve 82. The lower connector 9 may be provided with a pressure relief hole.

The working principle of the anti-seize hydraulic anchor 1 of the present invention will be described in detail with reference to fig. 1.

The first temporary locking piece 56 and the second temporary locking piece 83 each remain intact and exert a locking action during the lowering of the anti-sticking hydraulic anchor 1 string. Under the securing action of the first temporary lock 56, the two-way slip 71 is in a retracted state. During setting of the packer, under the action of a positive oil jacket pressure difference (the oil pressure is greater than the jacket pressure), high-pressure fluid (e.g., hydraulic oil) enters the inner cavity of the hydraulic cylinder 51. As the oil pressure gradually increases, when a set value or threshold value is reached, the first temporary lock 56, which is configured as a shear pin, is sheared, pushing the piston rod 52 to move in the axial direction of the base pipe 4 and to gradually extend from the hydraulic cylinder 51. The piston rod 52 compresses the return spring 62 and simultaneously drives the first cone 53 to approach the slips 71, so as to push the slips 71 to move in the radial direction of the central pipe 4 and extend out of the slip sleeve 72, and at the moment, the slips 71 are unfolded and embedded on the sleeve to realize anchoring. As the oil pressure increases, the anchoring force of the anti-sticking hydraulic anchor 1 also increases accordingly. When the pressure reaches the pressure required by the pipe column of the whole anti-blocking hydraulic anchor 1, the sealing of the anti-blocking hydraulic anchor is finished, and effective anchoring is started, namely, the anti-blocking hydraulic anchor enters a working state.

After the construction is finished, the pressure in the hydraulic cylinder 51 is discharged, the return spring 62 pushes the piston rod 52 and the first cone 53 to move and return in the direction away from the slips 71, and meanwhile, the slips 71 move in the radial direction of the central tube 4 and retract into the slip sleeve 72 due to the action of the return spring 73, so that the anchoring is released.

When the oil pressure in the hydraulic cylinder 51 is balanced with the pressure of the return spring 62, and the anchor cannot be released through pressure relief, or based on the selection of the operator, the forced anchor release by the external force can be realized by the second anchor releasing mechanism 8. Specifically, a ball (for example, a steel ball) is put into the ball seat of the temporary holding sleeve 82. After the ball falls into the tee, the blow continues until the second temporary lock 83, which is configured as a shear pin, shears. The temporary holding sleeve 82 moves in the axial direction of the center pipe 4 and away from the center pipe 4 until the stop surface formed by the outer wall of the temporary holding sleeve 82 engages with the stop step formed by the inner wall of the lower joint 9, and the temporary holding sleeve 82 stops moving. At this time, the pressure relief hole of the lower joint 9 is communicated with the internal oil path of the central pipe 4, so that impurities at the slips 71 can be washed circularly, and smooth anchor release is ensured. Preferably, the stop face of the temporary holding sleeve 82 is a ramp, while the stop step of the lower joint 9 also has a slanted stop face.

The pipe column of the anti-sticking hydraulic anchor 1 is lifted up, and the central pipe 4 drives the sleeve 81 and the elastic pawl 811 through threaded connection. The resilient detent 811 is pulled upward and the stop boss 814 is partially resiliently deformed and travels upward after passing over the end of the second vertebral body 64. At this point the upper joint 2 can bring the hydraulic cylinder 51 together with the piston rod 52 through the central tube 4 so that the first cone 53 can move away from the slips 71 to release the slips 71. The retraction space of the slips 71 is made free, and the slips 71 are retracted into the slip sleeve 72 under the action of the return spring 73, so that the forced releasing of the anti-blocking hydraulic anchor 1 is completed.

In the working process of the anti-blocking hydraulic anchor 1, the sealing ring arranged at the joint of each part can ensure the sealing performance of the anti-blocking hydraulic anchor 1 at high temperature and high pressure, and keep each part to work normally.

The anti-blocking hydraulic anchor provided by the invention can realize the following technical effects:

(1) the sealing ring and the gasket are combined and sealed, so that the sealing reliability under the high-temperature and high-pressure working environment is ensured. The anti-blocking hydraulic anchor has the advantages of large axial space, multiple sealing modes and good sealing effect.

(2) The sheet-shaped bidirectional slip is simple in structure, easy to implement, strong in anchoring force and small in damage to the sleeve. The bi-directional anchoring can withstand the tension and compression of the anti-seize hydraulic anchor string.

(3) By adopting the structure of the hydraulic piston and the reset spring, the anchoring-releasing action can be realized for a plurality of times, and the anti-blocking hydraulic anchor can be effectively anchored for a plurality of times.

(4) The hydraulic seat seal has wide application range and is not limited by well deviation.

(5) Meanwhile, the pressure relief automatic reset anchor releasing and external force forced anchor releasing (throwing and pressing anchor releasing) modes are provided, so that the selection is convenient, and the success rate and the reliability of the anchor releasing are improved.

The anti-blocking hydraulic anchor can overcome the problems that the conventional anti-blocking hydraulic anchor is easy to leak in a sealing way and is difficult to detach due to the fact that a fluke is blocked when the conventional anti-blocking hydraulic anchor is applied to an ultrahigh-temperature and ultrahigh-pressure acidic oil-gas field, has the advantages of being reliable in sealing, capable of repeatedly anchoring, capable of guaranteeing reliability through multiple anchor detaching modes and the like, and is suitable for the ultrahigh-temperature and ultrahigh-pressure acidic oil-gas field.

While various embodiments of the invention have been described herein, the description of the various embodiments is not intended to be exhaustive or to limit the invention to the precise forms disclosed, and features and components that are the same or similar to one another may be omitted for clarity and conciseness. The particular features, structures, materials, or characteristics of the various embodiments may be combined in any suitable manner in any one or more embodiments or examples herein. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

As used herein, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exhaustive, such that a process, method, article, or apparatus that comprises a list of elements may include those elements but do not exclude the presence of other elements not expressly listed.

Exemplary systems and methods of the present invention have been particularly shown and described with reference to the foregoing embodiments, which are merely illustrative of the best modes for carrying out the systems and methods. It will be appreciated by those skilled in the art that various changes in the embodiments of the systems and methods described herein may be made in practicing the systems and/or methods without departing from the spirit and scope of the invention as defined in the appended claims. It is intended that the following claims define the scope of the system and method and that the system and method within the scope of these claims and their equivalents be covered thereby. The above description of the present system and method should be understood to include all new and non-obvious combinations of elements described herein, and claims may be presented in this or a later application to any new and non-obvious combination of elements. Moreover, the foregoing embodiments are illustrative, and no single feature or element is essential to all possible combinations of features and elements that may be claimed in this or a later application.

Claims (10)

1. The utility model provides an anti-sticking hydraulic pressure hydraulic anchor, includes the center tube, its characterized in that, anti-sticking hydraulic pressure hydraulic anchor still includes:

an anchoring mechanism comprising slips movable in a radial direction of the base pipe to anchor or un-anchor;

a hydraulic actuating mechanism for driving the slips to anchor;

a first release mechanism for applying a force to the hydraulic actuation mechanism to move it away from the slips; and

a second un-anchoring mechanism for unlocking the base pipe from the anchoring mechanism to allow axial movement of the base pipe relative to the anchoring mechanism.

2. The anti-seize hydraulic anchor according to claim 1, wherein the slips are formed with two oppositely disposed inclined surfaces on a side thereof facing the base pipe;

the hydraulic actuating mechanism includes:

a first cone for moving in an axial direction of the base pipe to drive the slips, the first cone having a taper adapted to one of the two tapers; and

a second vertebral body disposed opposite the first vertebral body, the second vertebral body having a taper adapted to the other of the two bevels.

3. The anti-seize hydraulic water anchor according to claim 2, wherein the hydraulic actuation mechanism includes:

a hydraulic cylinder connected to the center tube, an inner cavity of the hydraulic cylinder being in fluid communication with an internal oil passage of the center tube;

a piston rod connected to the first vertebral body; and

a first temporary lock for holding the piston rod stationary relative to the hydraulic cylinder, the first temporary lock being breakable to allow movement of the piston rod in the axial direction of the center tube.

4. The anti-seize hydraulic water anchor according to claim 3, wherein the first temporary lock is a shear pin connecting the piston rod to the base pipe.

5. The anti-seize hydraulic anchor according to claim 3 or 4, wherein the first un-seizing mechanism comprises:

a spring housing connected to the hydraulic cylinder; and

and the return spring is clamped between the spring sleeve and the piston rod.

6. The anti-seize hydraulic anchor according to claim 2, wherein the second un-seizing mechanism comprises:

a sleeve connected to the center tube and having a resilient detent;

a temporary holding sleeve embedded in the sleeve;

a second temporary locking member for connecting the elastic pawl and the temporary holding sleeve;

wherein the resilient detent is sandwiched between the second cone and the temporary holding sleeve and the resilient detent cooperates with a stop formed between the second cone in an axial direction of the central tube, the second temporary locking element being breakable to allow the resilient detent to disengage from the temporary holding sleeve and the second cone.

7. The anti-seize hydraulic water anchor according to claim 6, wherein the second temporary locking member is a shear pin securing the resilient detent to the temporary retaining sleeve.

8. The anti-seize hydraulic anchor according to claim 6 or 7, wherein one end of the temporary retaining sleeve near the central tube has a tapered ball seat for receiving a ball dropped into the temporary retaining sleeve.

9. The anti-seize hydraulic water anchor according to claim 6 or 7, wherein the outer wall of the temporary holding sleeve is formed with a stop surface;

the anti-blocking hydraulic anchor comprises a lower joint which is sleeved on the second vertebral body and tightly propped against the second vertebral body, and a stopping step which can be matched with the stopping surface in an axial stopping manner is formed on the inner wall of the lower joint.

10. The anti-seize hydraulic anchor according to claim 9, including an upper sub fitted over the central tube with a washer disposed between the upper sub and the hydraulic actuator;

and sealing rings are respectively arranged between the upper joint and the central pipe, between the hydraulic actuating mechanism and the central pipe, between the sleeve and the second cone, between the second cone and the lower joint and between the lower joint and the temporary holding sleeve.

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